They are not going to kill off Emma.
I don’t think for a single second that Emma will really die. And I think her “villain” is really herself, with her walls, standing in the way of her own happy ending.
I think this is an interesting idea, because no matter how many times they say Emma does not have walls and that Hook and her family took down her walls, she obviously had them up this episode. I think the bigger question is what this says about Hook and Emma’s relationship. She obviously does not trust him enough to let him in at all. She hid the shaking of the hands, she hid the visions, she even refused to let him help her with the bird. How did Hook handle all this, he got angry and went drinking at a bar. No discussions, no hey I know something is wrong and I am going to make you talk about it, just Okay whatever I will go my way and you go yours.